1. Field of the Invention
The present invention relates generally to measurement and instrumentation systems and, more specifically, to measurement modules.
2. Description of the Related Art
Scientists and engineers often use measurement or instrumentation systems to perform a variety of functions, including laboratory research, process monitoring and control, data logging, analytical chemistry, test and analysis of physical phenomena, and control of mechanical or electrical machinery, to name a few examples. An instrumentation system typically includes transducers and other detecting means for providing “field” electrical signals representing a process, physical phenomena, equipment being monitored or measured, etc. The instrumentation system typically also includes interface hardware for receiving the measured field signals and providing them to a processing system, such as a personal computer. The processing system typically performs data analysis and presentation for appropriately analyzing and displaying the measured data.
Often, the field signals may be linked to high common-mode voltages, ground loops, or voltage spikes that often occur in industrial or research environments that could damage the computer system. In that case, the instrumentation system typically includes isolation circuitry such as opto-couplers for eliminating ground-loop problems and isolating the computer from potentially damaging voltages. Input measurement modules may be provided for conditioning the raw field voltage signals by amplifying, isolating, filtering or otherwise converting the signals to the appropriate digital signals for the computer system. As one example, the digital signals are then provided to a plug-in data acquisition (DAQ) input/output (I/O) board, or a computer-based instrument that is plugged into one of the I/O slots of a computer system. Generally, the computer system has an I/O bus and connectors or slots for receiving I/O boards. Various computer systems and I/O buses may be used to implement a processing system for receiving the measurements. The computer may receive measurements from multiple sources, where, for example, different sources may interface with the computer through respective input measurement modules.